For the bill to pass the House, a not insignificant number of the 39 Democrats who voted No in November must switch their votes to Yes. So far, however, we know only of Yes votes that Pelosi has lost or is about to lose -- Reps. Cao, Wexler, Murtha, and Abercrombie (at the end of the month). Rep. Jason Altmire, Democrat of Pennsylvania and a No vote, expressed his skepticism to the AP:

"This is how the whole thing started to begin with. We had a bipartisan summit at the same time last year, and we didn't end up in a very good place," said Rep. Jason Altmire, D-Pa., a moderate who voted against the health legislation in the House. "And that was when the political climate was much different" — more favorable to Democrats and Obama.

Doesn't sound like he's about to switch to Yes, does it?

One Republican congressman worries about an "Ambassador Strategy," in which Speaker Pelosi or President Obama promises goodies to retiring House Democrats to switch their votes to Yes. That might be enough to convince, say, Rep. Jim Tanner of Tennessee. But one switch won't be enough to pass Obamacare.